Cobot welding – Automation is easier than expected

Simon Opper

After his apprenticeship as an industrial mechanic at ABICOR BINZEL in 2010, Simon
Opper joined the company‘s prototype construction department. He later graduated
from the Weilburg Technology Academy with the degree of »State-certified technician in
mechanical engineering, specializing in construction and development«.

With the subsequent supplementary course in technical business administration, he has the right knowhow for the cobot product manager. He interacts in close cooperation with the customer, the qualified partners and all those involved in the company and provides holistic support for the product in the market.

Simon Opper
Junior Product Manager Cobot,
ABICOR BINZEL ROBOTIC SYSTEMS

We have always welded this by hand

Manual welding is the supreme discipline, no question about it at all. In particular, small batch sizes and complex components can be welded faster by a manual welder than by a robot. With a welding robot, the programming time must be taken into account, a manual welder, on the other hand, is completely self-sufficient and can start right away.

As soon as the lot size increases, at some stage a point is reached where an automated process becomes interesting – even necessary, if you don‘t want to waste time and money. The statement „We have always welded this by hand ...“ can then quickly lead to the fact that the specified number of pieces at the calculated costs can no longer be realized in the desired time. Then the competition is happy – and gets the job.

Maybe you are just standing on such a threshold where time and costs breathe down your neck. Perhaps you have already noticed that your employees lose interest in the monotonous work with increasing quantities, not to mention the decreasing quality. Under certain circumstances, you are in the middle of the situation that you have to retire experienced welding specialists and you lack qualified young people.

It is obvious: the current market situation – and even more intensely the future – calls for a rethink. None of us can avoid opening the door to automation technology.

However, many companies find it difficult to take the first step into automation because the robot is still seen as the enemy.

• Getting into automation is a big step
  Anyone who has previously only welded manually in their company and would like to switch to automation, must create conditions that mean a big step in change – for their own employees, the existing systems in production and also for safety.
• There are still too many individual welding jobs
  If most orders consist mainly of small batches and complex components, the manual welder is the measure of all things. A robot only brings advantages when the lot sizes increase, because fixtures have to be created and the robot has to be programmed first and that »eats up« time and thus costs.
• Investment costs … and those afterwards
  It is not only the investment costs for a welding robot, but also those that are still incurred after the purchase, such as those for the training required to operate the robot. This may also mean having to increase staff such as for example trained robot programmers. Therefore, new know-how is needed.

• Required complex safety technology
  The use of a welding robot requires defined safety technology so that people in the vicinity of the robot are not exposed to any danger. You have to get intensive information about these and also provide the appropriate area. UV radiation, welding fume and a possible collision between humans and robots must be avoided.
• Fear of job loss
  Who doesn‘t know the images of production lines, where more robots can be seen than busy people? This often implies that a welding robot will take away the job ofone or even several manual welders.

Manual welding

The flexibility is greatest with manual welding, as the manual welder can adapt very well to changing component geometries. This is a great advantage, especially where workpieces are welded very individually, for example on construction sites when welding staircase railings, balustrades, bridges, etc. But also when repairing vehicles and the like. Often mechanisation or even automation is not possible here. Investment costs are around 2,000 to 3,000 euros.

Due to human influence, the quality can vary. With repetitive tasks, the quality of the welding result will change slightly from component to component. Even an excellent manual welder has a bad day or the constant monotonous work leads to fatigue over a working day. The result is usually already visible on the surface of the seam and can lead to complaints in the case of visible seams.

Manual welding will be very economical if no other processes, i. e. no automation, are possible, for example, if the component is very complex. If the number of batch sizes increases, the profitability compared to automated processes decreases accordingly.

Mechanised welding

Mechanisation is typically used when welding components with simple geometries such as longitudinal seams or round seams with increasing batch sizes. These are one to two-dimensional linear undercarriage and tilt-turn tables with automatic torch feed. The given hardware severely limits the flexibility, only changes in length or diameter can be varied. The welding quality is consistently constant. If, in individual cases, manual intervention to correct the position and the parameters is necessary, this is possible with these systems.

The economic efficiency of these systems is quite good due to the low investment, but manual support is sometimes necessary for this. Investment costs for mechanised welding are between approx. 5,000 euros and 25,000 euros.

Robot welding

Before we get to the cobot, let‘s first look at automated welding with a conventional industrial robot. Today, robot welding systems are used wherever high quantities of constant quality are required at 100 %. The cost pressure on the manufacturer is very high due to the increased competition. Typical users are the automotive industry (body construction) with its suppliers (axles, exhaust-gas systems, seats), heavy machinery construction (earthmoving machines, trucks, wagon construction) but also other industries such as for example scaffolding, switch cabinet production, manufacturers of steel furniture, fitness equipment etc. The quite high investment for the acquisition of a welding robot, for which you have to calculate between approx. 80,000 euros and 120,000 euros, pays off quickly due to the producible quantities. As a result, the economic efficiency is also well in the upper range. Since a robotic welding cell consists of fixed automated devices and complex programs, the flexibility is not so high.

Cobot welding

Over the past years, after a triumphant advance in assembly and handling, cobots have gradually gained ground in welding technology. For the user groups, these are mainly small and medium-sized companies.

Cobots are used where small to medium quantities have to be welded and where the size and geometry of these changes again and again over time. If you consider that cobots represent an automated process, the flexibility is very high: programming and operation are easy to learn and implement. With simple part geometries, fixtures for components can be manufactured or adapted quickly. As with all automated processes, the constant quality of the weld seams is very high. Although the costs for a cobot can almost be equated with those for industrial robots, the investment of 60,000 euros to 80,000 euros is low due to simple devices and very fast availability. This means a high level of economic efficiency.

An analysis by the International Federation of Robotics (IFR) in cooperation with the Fraunhofer Institute for Production Technology and Automation (IPA) from 2019 shows that more than half a million new robot systems are currently put into operation every year. For small and medium-sized production companies, this means that if you want to keep up, you must also invest in automation. In addition, the need for this becomes even clearer when you take a closer look at the development of the available labor force: in 2013, there were still around 44 million available, but this is expected to drop to 40–42 million by 2030. These figures make it painfully clear that companies have no other option than to invest in automation if economic strength is to be maintained.

The previous chapter has already made it obvious why conventional industrial robots do not make sense in every manufacturing company and why the step into full automation is associated with many questions, uncertainties and hurdles. In addition, there is the quite natural further development of products. On average, these are optimised at ever shorter intervals, i. e. after only about two to three years. In practice, these facts mean that robot technology must also become more flexible.

Cobots cannot only meet the increased demand for flexibility, they can also really score points in terms of profitability and payback period.

Manual welding and robot welding in comparison

A robot-welded seam meets the requirements for consistent quality – whether it is good or bad. The welding performance of the robot can only be as good as it is programmed. In direct comparison, any experienced manual welder can produce a weld seam which is absolutely comparable to that of a welding robot. However, even the best and most persistent manual welder gets tired and cannot provide exactly the same high-quality weld seam as with the first component as the number of pieces increases – which is only natural for humans. In this respect, the robot has clear advantages and welds with the same quality even after hours, if the process runs smoothly. The same applies to welding with a cobot.

Flexibility: Just show once is enough

One of the biggest advantages of welding with a cobot – and not only for small and medium-sized companies – is its flexibility. Especially for welding companies with different welding tasks. The cobot is »shown« the welding task once and literally gets going. Once a welding task has been programmed, it is stored, can be assigned to the device and can be recalled at any time if required. In this way, it is always quickly available for repetitive jobs. Set-up costs are reduced and productivity is increased.

The simple programming allows a quick »changeover« to the next small series. Many users have a large number of components with associated robot programs and fixtures which they can quickly access if necessary.

To access the video »ROBiPAK – Welding equipment for Cobots«, simply click on the picture or scan the QR code.

Therefore, we are treading water ...

Do you know this from your company?

• Well-trained and experienced welders have to do more and more work for which they are actually overqualified
• Your quantities are still too small for an industrial robot, so that an investment in this direction is not worthwhile
• You have only welded manually up to now and would like to relieve your employees, also because the quantities are constantly increasing
• You also weld in several layers and this is a real torture for your employees
• You have already thought about automation, but shy away from the initial costs
• Your applications are very special and yet they recur
• Your welders have been complaining for some time about one-sided, repetitive welding work and have reached their limits – physically and emotionally
• The fear of job loss is very great, even though the increasing numbers of units can no longer be achieved with manual welders
• You must be 100 % convinced before you invest in robot technology

What is the best way to get started?

You may start your search with research on the internet, where experience shows that many questions arise. You may already get initial answers from your trusted distributor. If you have already found a supplier for a complete solution with a cobot, the contact details of their office and field service will also help. Often suitable partners can also be reached via social media channels. If you are interested in working with ABICOR BINZEL, you will find the contact details at the end of this eBook.

What are our possibilities – no more options?

In order to provide you with a reasonable concept for your cobot solution, we will examine current workpieces in your production together with you:

• Do you have many not OK (NOK) parts?
• Do you already have clamping fixtures?
• How are the components prepared for welding (seam preparation)?

1. Analyse components brought along
2. Define parameter specifications
3. Determine welding sequence with the cobot
4. Clamp the component

5. Programming of the cobot
6. Welding process
7. Joint evaluation of results
8. Discussing optimisations

Who is needed? The team for the fine-tuning

How is a cobot welding system set up? This is a short, but at the same time an important question, because it is about your safety, the safety of your colleagues and also about the legal basis.

This is how your ideal cobot can look like

Let us assume that we have jointly test welded your components and prepared a feasibility analysis. This data now serves as a basis for the qualified partner who contributes table, fixture and housing for the complete solution. As a result you will see what the optimal cobot can look like for you, for example:

• as a combination with a welding table
• suspended mounted
• with turning devices
• with a longitudinal seam travel range or a linear unit
• with fume extraction
• with cleaning station

When planning a cobot, all those involved work closely together – then »it runs smoothly«

Here we go ...!

Your cobot is planned, you are not the marketer and the order has been placed. Once the whole process has been completed, the next step is for your qualified partner to set up your cobot system. Ideally together with you or the persons responsible in your company, who can deal with the cobot in detail. The installation of a cobot system can be completed within one working day. This means that the first training for you or your employees or colleagues can take place on the same day.

What happens after the cobot is put into operation?

You are in regular contact with the distributor you trust, our partner. He is always involved and informed throughout the entire process. Especially, after the installation of your cobot, he remains your first contact person in all matters, such as the supply of wear parts. The same applies to the contact with the qualified partner who has installed the cobot together with the equipment in your company in conformity with CE standards. ABICOR BINZEL is in close contact with your contact persons via the sales representatives.

Certainly you can contact ABICOR BINZEL for other solutions and welding technology
enquiries. If welding parameters need to be optimised after installation, we will of course
be happy to assist you.

How to get the most out of your cobot welding system

When investing in a cobot welding system, of course you want to get the most out of it. The right equipment is one thing, the right operation and the handling of this welding system in busy everyday life is quite another. With the services described below you will be able to use your cobot to its full effectiveness – provided that they are optimally coordinated:

When choosing your service provider, make sure that these aspects are covered and interlock optimally. Should you decide to work with ABICOR BINZEL, you will have a partner at hand with whom all the pieces of the puzzle fit together perfectly so that you get the maximum benefit from your cobot system.

These services get the most out of your cobot welding system

The customer service in a cobot project

Especially in a cobot project the customer service is involved in the planning from the very beginning. This enables specialist departments and partner system houses to respond jointly to your wishes and requirements at an early stage.

The following figure shows the individual steps and responsibilities from the planning of a
cobot project at ABICOR BINZEL up to the maintenance of the system after implementation, which is also carried out by the qualified partner. It may sound like a lot, but based on our experience it is a fast and smooth process.

Please consider two important aspects when planning your cobot welding system:

• Involve your employees in the process so that they do not regard the cobot as an enemy, but as a valuable helper who can relieve them.
• Take a little more time at the beginning to achieve the best result at the end.

Interaction of ABICOR BINZEL (magenta) and
partner system houses (blue)